Power Vs Heart rate

Until you really use power it is really hard to outlay the earned $$, when you really don’t know what you are getting. So I thought I would show a data plot to try to outline the benefit. Last week I did my FTP test and although I did the best I could, I could have finished with a higher number if I was more consistent with my power output, but really did not know a solid number to aim for. Yesterday I did an interval set, with the aim to keep my power consistent and at the right level. I think I nailed it (I know my number’s aren’t that high, only got a little engine ;)), and pushed my limits, although my legs did show signs of fatigue towards the end (power fluctuations). When you look at the data you can see the benefits of power quite clearly. So here it is (BTW click on the pic to enlarge):

As you can see I did lots of short intervals ranging in time but incorporated it into 4 major sets. My power (yellow) was very consistent across 3 sets and only dropped a little in the 4th where my cadence (green) was increased to over 100rpm. The first 2 major sets I kept my cadence the same and increased it a little in each of the last 2 sets. My Heart rate (red) increased throughout the whole first set (10min), then remained steady for the second set. The 3rd and 4th sets Heart rate increased throughout and followed my power level to some extent, the heart rate increased compared to the first 2 sets was due to the increase in cadence.

In any interval set you want to keep consistent throughout the whole set (unless there are planned surges), in my first set it took 8-9 minutes till I my heart rate caught up to my power output. If I was working from my heart rate I would no doubt have been pushing too hard at the beginning and then not hard enough towards the end. Even in the 2nd set after a 3 minute recovery it took a minute to rise and was not till I went a little harder (harder than I should have) that it rose to the right level. So especially short intervals or sets where you are not totally warmed up you will not have a consistent output. Heart rate can also be influenced by fatigue or stress; you may find working with Heart rate some days it just does not go up even though your perceived effort feels like it should be higher. Without power you will never truly know what your effort is, there is always the heart rate delay, and in-consistency’s for it to be used as a measure.

In summary there are benefits to both. Heart rate shows the body’s response to the effort and other stress’s in life, while power is the right tool for intervals and being consistent, measuring efforts, and testing for improvements. But it is not till you work with both till you have the right tools to answer your question’s as long as you have right knowledge, know your limits, you should have a good chance of stopping yourself from over-training or at the other end train that bit harder to get the most out of yourself.

Now I’m no expert just the things I have picked up from my own experiences and reading, but hopefully if someone is thinking of going with power hopefully I have answered some questions. For reference I used my ibike on the trainer setup specifically for that trainer so values are accurate, I currently also use a powertap on the mountain bike. To be honest in the future I would only buy a “true” power meter like the Power Tap or SRM or Quark or Metrigear that either use torque or strain gauges. It seems all other units need to be setup accurately and calibrated correctly which is very hard to do, how can you tell if it is correct or not? The MetriGear unit I really like measured at the pedal with lots of torque sensor’s to indicate the angle and force of every point on each pedal stroke, you got to love that. Check this out for the geeks ;) http://www.metrigear.com/news/ have a look at the pedal force profile link, hopefully it will be released soon. Torque will be the next thing after power without a doubt, for high power outputs you need to be efficient don’t you, and being able to check these values for each leg is another bonus.

Now does it all work and make you much better compared to just listening to your body don't know there are alot of awesome riders out there without all this data, and insead of looking at it maybe we should just ride ;).

FTP's what the???

OK, I know some of you might not have any idea about this bike training geek talk so I thought I would run through a brief description.

FTP stands for Functional threshold power which does not help much. FTP is the normalised power that a rider can maintain for 1 hour, and is given as a unit of watts. It is something that is hard to get an accurate figure on. The easiest way without blowing yourself up too much is to do a 20min time trial on a consistent slight uphill rise, these are hard to find. After the 20min TT, you multiply your average power (not normalised power) by 0.95 this will give you a close enough FTP. So some may ask what is the difference between normalised power and average power. Average power includes all the stopping and starting whereas Normalised takes an average but removes all of the stopping and times you are not really producing power.

So the point of knowing your FTP is so that you can perform accurate intervals at a known power output. You can also use these numbers if you were in a race, say if you gapped the field and wanted to sit at a pace you could maintain you would try to sit close to your FTP if you had about 1 hour left of racing. As I don’t really road race I use the FTP for intervals. I receive my program from my coach on what I should be doing in each interval, 3min at 110% of FTP, 3 min rest, 2min at 115% of FTP, 2min rest etc, etc. Each interval set is planned to work at your limits for your own specific goal without overdoing it.

So that is a little insight to my training, and it is tough very tough. It has been my last 3+ months and I have been showing an increase in much needed speed, endurance I have not tested yet. Really it is all about pushing the limits in both power output and endurance. Intervals are a great way to train but doing it with power really steps it all up to another level.

Well I have another little trick that I have up my sleave, but it is all to do with my power meter. My power meter is all software based, and I can pre-program my interval sets. So I put them all in the meter go and do them with my meter telling me how long and what power I should be at, I can see my average power for that interval to make sure I am on target. So I can do my best to meet all target while out on the bike, I don’t have to wait till I get home and download the data to see that I pushed it too hard in my first set, and failed for the last 3, I actually know as I am riding. I also enter my FTP value into the meter and I can see my training stress score or the intensity factor, or my average normalised power for that ride. These features are what sets apart my ibike apart from other power meters. Although the ibike maybe slightly inaccurate depending on how you calibrate it, once you have it right it is a great bit of training kit.

So has this type of training worked for me yet? I don’t know but it makes me extremely tired if that counts, but I will find out in a few weeks ;).